Liquid End; Bleed Valve And Integrated Relief Valve - ProMinent Sigma X Operating Instructions Manual

Functional description

5.2 Liquid end

5.3 Bleed valve and integrated relief valve

Bleed valve
Integral relief valve
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The diaphragm (2) hermetically shuts off the pump volume of the dosing
head (4) towards the outside. The suction valve (1) closes as soon as the
diaphragm (2) is moved in to the dosing head (4) and the feed chemical
flows through the discharge valve (3) out of the dosing head. The dis‐
charge valve (3) closes as soon as the diaphragm (2) is moved in the
opposite direction due to the vacuum pressure in the dosing head and
fresh feed chemical flows through the suction valve (1) into the dosing
head. One cycle is thus completed.
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4
Fig. 9: Cross-section through the liquid end
1 Suction valve
2 Diaphragm
3 Discharge valve
4 Dosing head
5 Backplate
13 Safety diaphragm
Turning the rotary dial (3) on the bleed valve to "open" causes it to open
and the liquid end can be bled. Or it is used as a priming aid for priming
against pressure. The feed chemical flows out through the hose connec‐
tion (5), e.g. into a storage tank.
The integral relief valve operates in the "close" position as a simple,
directly controlled relief valve. As soon as the pressure exceeds the pres‐
sure value, which is preset using the large spring (1), it lifts the ball (2).
The feed chemical flows out through the hose connection (5), e.g. into a
storage tank.
The integral relief valve can only protect the motor and the gear, and then
only against impermissible positive pressure that is caused by the
metering pump itself. It cannot protect the system against positive pres‐
sure.
The integral relief valve works as a bleed valve as soon as the rotary dial
(3) is turned to "open": The valve opens and the liquid end can be bled. Or
it is used as a priming aid for priming against pressure.
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